The investigators propose secondary analyses of Premier, Inc., data to pilot the Premier data base as a resource for studying inpatient medication patterns in the pediatric population. This aim will be accomplished in three steps: 1) We will expand beyond an earlier analysis of a regional population of hospitalized children to obtain national estimates of pediatric inpatient medication use. We will replicate an analysis of inpatient medication use conducted using the Nemours/The Alfred I DuPont Hospital for Children data base, and using data collected by Premier, Inc., to obtain national estimates of pediatric inpatient medication use by specific drug, age sub-group, sex and race/ethnicity;2) We will then validate the national estimates calculated from the Premier, Inc., data base, by comparing characteristics of hospitalizations in the Premier, Inc., database to characteristics of the HCUP KID 2006 national data base of pediatric hospitalizations, a probability based sample of pediatric hospitalizations;and 3) We will test hypotheses regarding inter-hospital variation in medication patterns by studying three groups of medications, as examples of medications that may vary in usage from one hospital to another. We propose to study variation in use of inotropes in neonates, pain medications (particularly morphine) in children under 18, and vancomycin administration in children under 18. These aims relate to the AHRQ mission of improving the quality, safety, efficiency and effectiveness of health care. In particular, children's health care will be improved by understanding patterns of medication use in hospitalized children, by describing baseline estimates of usage, and by estimates of variation (and sources of variation) in usage. These analyses will lay the basis for future studies of comparative effectiveness and can contribute to the design of clinical studies. The measurement of baseline levels and sources of variation in medication practices can also be used in future studies to measure and reduce medical errors, improve quality of care, and describe off-label medication use in hospitalized children, all of which are essential to improving efficacy and safety of medication practices in the inpatient pediatric population. PUBLIC HEALTH RELEVANCE: As with other aspects of medication use by children, measurement of pediatric population trends in use presents challenges that differ from those in adult populations. In general, out-patient drug data and inpatient drug data are not provided in the same data base, and it is often not possible to link inpatient and outpatient use for the same patient. Thus, separate methodology is needed in measuring outpatient and inpatient use. An analysis of the Premier, Inc., database has the potential to produce estimates of inpatient use and variation in patterns by hospital. These analyses will lay the basis for future studies of comparative effectiveness, may contribute to planning and design of observational and clinical studies, and can also be used in future studies to measure and reduce medical errors, improve quality of care, and describe off-label medication use in hospitalized children. These can in turn inform the full range of policy and practice decisions, including drug labeling, warnings, and removal from the market, which require an understanding of the number of children affected, their ages, and other patterns of use.